Investigation on Kinetics and Degradation Mechanism of Methyl Orange Wastewater Treatment Using a Supported Three-Dimensional Electrode
The Fe3O4-MnO2/GAC particle electrode was prepared by chemical coprecipitation method.The reaction kinetics of methyl orange and COD degradation was studied by using three-dimensional electrode system.The degradation mechanism of methyl orange was analyzed by UV-visible spectrum.The results showed that both the degradations of methyl orange and COD were first-order reactions,and the reaction rate constant was maximum when the particle dosage was 50 g·L-1,the solution pH was 7 and the solution temperature was 45.The activation energies of the degradation of methyl orange and COD were 3.444 2×104 J·mol-1 and 1.529 9×104 J·mol-1,respectively.In addition,according to UV-visible spectrum,the degradation mechanism of methyl orange was estimated to be azo degradation.The contact between strong oxides and methyl orange first broke the cyclic chromophore group and broke the azo bond to decompose into various aromatic substances.Then·OH further attacked the large π bond of the benzene ring,forming intermediates such as phenol and hydroquinone,which were finally mineralized into CO2 and H2O.